California

Patent attorneys in California

California hosts 9,567 active patent practitioners registered with the USPTO Office of Enrollment and Discipline. Patent attorneys and patent agents can both prepare and file patent applications, but only patent attorneys can also offer legal advice on prosecution strategy, freedom-to-operate analyses, and infringement opinions in California. Practitioners are concentrated across 20 cities, with the largest clusters in the metros listed below. Notable firms with multiple registered practitioners in the state include Joseph C. Harkins Esq, Genentech, Inc, and American Patent and Trademark Law Center Inc..

Top cities in California

All practitioners in California

Joseph C. Harkins

Reg. 78161
Patent attorney

Joseph C. Harkins Esq

San Diego, CA · 92102

858-565-4585

Joan C Harland

Reg. 51779
Patent agent

Oakland, CA · 94611

510-338-0548

Susan L Harlocker

Reg. 59144
Patent agent

Genentech, Inc

South San Francisco, CA · 94080

650-303-6934

Donn K Harms

Reg. 38911
Patent attorney

American Patent and Trademark Law Center Inc.

Del Mar, CA · 92014

858-509-1400

Albert J Harnois· Jr

Reg. 46123
Patent attorney

Cavium, INC

San Jose, CA · 95131

408-943-7641

Rosalio Haro

Reg. 42633
Patent agent

Epson Research and Development, Inc.

San Jose, CA · 95131

408-952-6131

Victor M Haroldsen

Reg. 70295
Patent agent

West Sacramento, CA · 95691

530-902-3008

Sohrab Haroonian

Reg. 50950
Patent attorney

Sohrab Haroonian

Van Nuys, CA · 91401

818-785-6733

Burch A Harper

Reg. 42635
Patent attorney

Kateeva, Inc.

Newark, CA · 94560

800-385-7802

Laura A Harper

Reg. 80886
Patent attorney

Omni Legal Group

Los Angeles, CA · 90067

310-276-6664

Marilyn Harper

Reg. 67677
Patent attorney

Concord, CA · 94520

775-232-8021

Kelly A Harradine

Reg. 69153
Patent attorney

BioMarin Pharmaceutical Inc.

Novato, CA · 94949

415-382-5111

Kyla L Harriel

Reg. 41816
Patent attorney

Jackson and Co, LLP

Oakland, CA · 94611

510-652-6418

Jason Daniel Harrier

Reg. 60964
Patent attorney

Plaid

San Francisco, CA · 94103

202-641-5607

John David Harriman· II

Reg. 31967
Patent attorney

Foundation Law Group

Los Angeles, CA · 90071

424-236-3911

Curtis Lamar Harrington· Jr

Reg. 31456
Patent attorney

Harrington & Harrington

Long Beach, CA · 90809-1719

562-594-9784

Irvin C Harrington· III

Reg. 44740
Patent attorney

Agoura Hills, CA · 91301

Jack R Harris

Reg. 51145
Patent agent

Haverstock and Owens LLP

Sunnyvale, CA · 94086

408-530-9700

James E Harris

Reg. 40013
Patent attorney

Rambus Inc.

Sunnyvale, CA · 94089

408-462-8539

James M Harris

Reg. 52995
Patent agent

Palo Alto, CA · 94306

650-323-4059

Joel M Harris

Reg. 44743
Patent agent

InCube Labs

San Jose, CA · 95131

408-457-3714

Jonathan J W Harris

Reg. 83997
Patent agent

San Jose, CA · 95125

650-919-4476

Michael R. Harris

Reg. 71038
Patent attorney

Qualcomm Incorported

San Diego, CA · 92121

858-845-8555

Michael D Harris

Reg. 26690
Patent attorney

SoCal IP Law Group LLP

Westlake Village, CA · 91362

805-497-3488

Scott C Harris

Reg. 32030
Patent attorney

Law Office Of Scott C Harris

Rancho Santa Fe, CA · 92067

858-756-7778

Joshua C Harrison

Reg. 45686
Patent attorney

Joshua Harrison

Huntington Beach, CA · 92615

714-342-2391

Julie R. Harrison

Reg. 81122
Patent agent

Huntington Beach, CA · 92646

714-206-1553

Michael L Harrison

Reg. 26734
Patent attorney

Michael L. Harrison Attorney at Law

Los Gatos, CA · 95032

408-829-6397

David J Harshman

Reg. 29074
Patent attorney

Toshiba America Information Systems, Inc.

Irvine, CA · 92618

949-583-3515

Candace H. Hart

Reg. 79447
Patent attorney

Sinclair Braun Kargher LLP

Sherman Oaks, CA · 91403

213-429-6121

Common questions

Do I need a patent attorney based in California?
No. Every USPTO-registered patent practitioner is licensed to file applications on behalf of inventors in any state, regardless of where the practitioner's office is. Choosing a California-based practitioner can simplify in-person inventor signings, local meetings, and same-time-zone calls, but it is not a legal requirement.
How many patent attorneys are licensed in California?
9,567 active USPTO-registered patent practitioners list a California office address on the OEDCI roster. This includes both patent attorneys (who can also offer legal advice) and patent agents (who can prepare and file patents but not offer broader legal advice).
What is the difference between a patent attorney and a patent agent?
Both pass the USPTO Patent Bar and can prepare, file, and prosecute patent applications. Only patent attorneys also hold a state bar license, meaning they can additionally offer legal advice on infringement, licensing, and litigation strategy. Patent agents tend to charge less per hour and are common at large in-house IP departments.
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